This invention relates to heat exchangers and, more particularly, to an improved high temperature fluid-to-fluid heat exchanger.
Fluid-to-fluid heat exchangers are typically designed in accordance with the principles of forced convection heat transfer. Convection heat transfer is entirely dependent upon the fluid dynamics and associated turbulence of a particular process. Moreover, at high temperatures, such as those in excess of about 850.degree. C. (1562.degree. F.), forced convection becomes inefficient. Very high temperature processes also lead to other heat exchanger design problems due to loss of material strength, thermal stress and material reactivity, limiting the materials and hardware configurations that can accommodate such temperatures.
The foregoing problems become particularly acute in connection with high temperature gas-to-gas heat exchangers. Thus, typical prior art gas-to-gas exchangers, such as those used in flue gas recovery systems, are not very efficient where temperatures in excess of about 850.degree. C. (1562.degree. F.) are encountered.
Attempts have been made to construct high temperature heat exchangers, i.e., fluid-to-fluid or gas-to-gas heat exchangers, capable of operating at temperatures in excess of 850.degree. C. Known prior art heat exchangers, however, have typically suffered from fabrication difficulties and are very difficult to operate and maintain. Moreover, such heat exchangers have typically been easily damaged, suffer from frequent breakdowns due to severe thermal stress, and are very expensive to construct.
It is an object of the present invention to provide an improved fluid-to-fluid heat exchanger.
Another object of the invention is to provide an improved fluid-to-fluid heat exchanger capable of successful operation at temperatures in excess of about 850.degree. C.
It is a further object of the invention to provide a heat exchanger capable of operating at very high temperatures which is relatively compact and inexpensive to construct and maintain.
Other objects of the invention will become apparent to those skilled in the art from the following description.